In modern communication systems such as, for example wireless metropolitan area network (WMAN) e.g., WiMAX and/or cellular systems e.g., Long Term Evolution (LTE), advanced communication technologies may be used.
A WiMAX station which operates according to the Institute of Electrical and Electronics Engineers (IEEE) 802.16e/m standards may use Multiple Input, Multiple Output (MIMO) techniques to transmit pilot signals over the uplink (UL). The pilot signal may include plurality of resource units (RU). An UL Physical Resource Unit (PRU) is the basic physical unit for resource allocation. The PRU may include Psc consecutive subcarriers by Nsym consecutive Orthogonal Frequency Division Multiple Access (OFDMA) symbols.
The unit size of outer permutation in UL subcarrier to resource unit mapping is N PRUs. The outer permutation may support at least one granularity values, and/or multiple granularity values. As a consequence, it causes a performance trade-off between scheduling gain and diversity gain.
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